两种空气/煤油燃气发生器富油燃烧组织方案对比

根据空气/煤油富油燃烧的特点,提出了两种空气/煤油燃气发生器富油燃烧组织方案,设计了采用钝体稳定火焰和旋流空气、二次喷注空气稳定火焰的两种燃气发生器.为了对比两种方案的点火和燃烧特性,对两种燃气发生器进行了一系列热试,结果表明余氧系数是燃气发生器最重要的工况参数.随着余氧系数的增加,燃气发生器的状态逐渐从启动失败变为中途熄火,最终呈正常启动状态.采用钝体稳定火焰的燃气发生器稳定工作的余氧系数边界为0.518,采用旋流空气和二次喷注空气稳定火焰可将该边界延伸到0.237,极大地扩大了燃气发生器的工作范围.与钝体稳定火焰的燃气发生器相比,旋流空气和二次喷注空气稳定火焰的燃气发生器的富油燃烧的燃烧效率提高了20%.两种方案结构复杂性相当,旋流空气和二次喷注空气稳定火焰的燃气发生器不需要冷却火焰稳定器,可提高燃气发生器的工作时间. 

Comparison of two fuel-rich combustion schemes in air/kerosene gas generator

Two fuel-rich combustion schemes in air/kerosene gas generator were provided, and two gas generators with flame stabilized by bluff-body, swirling air and second air injection respectively were designed based on the fuel-rich combustion characteristics of air/kerosene. A series of hot fire experiments were conducted with two gas generators to compare the ignition and combustion characteristics of the two schemes. The results show that excess oxidizer coefficient is the most important working parameter in gas generator. With the increase of excess oxidizer coefficient, the states of gas generators vary from start failure to abnormal shut up, and finally to normal start. The range of stable working excess oxidizer coefficient in bluff-body stabilized gas generator is 0.518, and can be expanded to 0.237 by stabilizing flame through swirling air and second air injection, which greatly increases the working range of gas generator. The fuel-rich combustion efficiency of swirling air and second air injection stabilized gas generator is 20% higher than that of bluff-body stabilized gas generator. As the complexity of the two schemes is comparable, swirling air and second air injection stabilized gas generator could have a longer working time without cooling the flame holder.